diff --git a/src/Network/FKOAuth1.php b/src/Network/FKOAuth1.php
index 768cae7d1..31960a91d 100644
--- a/src/Network/FKOAuth1.php
+++ b/src/Network/FKOAuth1.php
@@ -10,6 +10,7 @@ use Friendica\Core\System;
 use Friendica\Database\DBM;
 use Friendica\Network\FKOAuthDataStore;
 use dba;
+use OAuthServer;
 
 require_once "library/OAuth1.php";
 require_once "include/plugin.php";